/Engine/Plugins/Editor/ContentBrowser/ContentBrowserClassDataSource/Source/ContentBrowserClassDataSource/Public/ContentBrowserClassDataSource.h
This function must be able to answer the question quickly or not at all (and assume visible). Itmust notblock doing something like a file system scan.
virtual bool IsFolderVisible ( const [FName](API\Runtime\Core\UObject\FName) InPath, const EContentBrowserIsFolderVisibleFlags InFlags )